JP3190368B2 - Endoscope image data compression device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope image data compression apparatus having improved compression efficiency of a subject image.

[0002]

2. Description of the Related Art In recent years, endoscopes (scopes or fiberscopes) capable of diagnosing or examining internal organs and the like by inserting an elongated insertion portion into a body cavity have been widely used. I have. In addition, not only for medical use but also for industrial use, boilers, machines, chemical plants, etc.
Alternatively, it is used for observing and inspecting an object inside a machine or the like. Further, various types of electronic endoscopes using a solid-state imaging device such as a charge-coupled device (CCD) as an imaging unit are also used.

An image recording apparatus for recording the video signal of the above-mentioned electronic endoscope apparatus on a large-capacity storage medium such as an optical disk or a magneto-optical disk and using it for diagnosis and investigation after the end of observation has been put into practical use. ing.

For example, FIG. 12 is a schematic view of an entire endoscope system including an image input device using the electronic endoscope device and the image recording device. The endoscope 61 inserted into the living body 62 is connected to the observation device 63. The observation device 63 is connected to an image recording device 66 including an observation monitor 64 and an endoscope image data compression device.

FIG. 13 shows a flow of an image signal in an image input device using the endoscope 61 and the observation device 63. An image signal from the CCD 71 at the tip of the endoscope 61 enters an amplifier 72 and is amplified to a voltage level within a predetermined range. After that, it enters the γ circuit 73 and is γ corrected. In the case of the RGB plane sequential method, the signal after the γ correction is converted into an analog-digital signal by an A / D converter 74, and then enters a selector 75, where an R memory 76
It is stored in each memory 76 of the R, G memory 76G and B memory 76B. The image signals stored in the R memory 76R, the G memory 76G, and the B memory 76B are called at the timing of the TV signal, and the signal processing circuit 77 determines the number of pixels of the CCD 71 by the monitor 64.
, And are subjected to digital-to-analog conversion by the D / A converters 78R, 78G, and 78B. The R, G, and B image signals that have been converted into analog signals are sent to RGB output terminals R, G, and B together with the synchronization signal (SYNC) of the synchronization signal generation circuit 80. The RGB signals obtained in this manner are displayed on the monitor 64 for endoscopic observation. The RGB signals can be recorded by the image recording device 66.

The light guide 84 of the endoscope 61 includes:
By passing the white light of the lamp 82 through a rotary filter 83 rotated by a motor 79, red, green and blue transmission filters forming a rotary filter are interposed in the optical path,
Light of each wavelength of red, green, and blue is emitted. Therefore,
The image signal captured under each of the red, green, and blue illumination light is
The R memory 76R, the G memory 76G, and the B memory 76
B is written. The motor 79 and the A / D
Converter 74, selector 75, R memory 76
R, G memory 76G, B memory 76B, the signal processing circuit 77, the D / A converters 78R, 78G, 78
B, The synchronization signal generation circuit 80 includes a control signal generation unit 81
Is controlled by

FIG. 14 shows a flow of an image signal in the image recording device 86. The RGB signal output terminal of the observation device 63 The image signals from the children R, G, B are input to the input unit 87 of the image recording device 86. The RGB signals are converted from analog to digital by an A / D converter 88 via a changeover switch, and then guided to a compression circuit 89. The compression circuit unit 89 is constructed based on a compression theory such as predictive coding. The compressed image data is recorded on a recording system unit 90 such as an optical disk or a magneto-optical disk. When reproducing an image, the recording system unit 9
The image data on 0 is restored to the original image signal in the expansion circuit section 91. After that, the digital-to-analog conversion is performed by the D / A converter 92 and sent to the output unit 93. On the other hand, there is a control signal generator 94 for controlling the destination of the image signal and the transfer timing at the time of transferring the image signal. This is connected to the A / D converter section 88, the compression circuit section 89, the recording system section 90, the expansion circuit section 91, and the D / A converter section 92. A synchronization signal (SYNC) is sent from the control signal generator 94 to the input unit 87 and the output unit 93.

FIG. 15 shows an image pickup surface 71 'of the CCD 71.
And the number of pixels on the display surface 64 ′ of the monitor 64. The number of pixels in the horizontal direction of the imaging surface 71 'is X
c, the number of pixels in the vertical direction is Yc, and the display surface 84 ′
If the number of pixels in the horizontal direction is Xm and the number of pixels in the vertical direction is Ym, there is a relationship of Xm> Xc, Ym> Yc, and the difference between Xm and Xc and the difference between Ym and Yc are determined by the signal processing circuit. Interpolation processing is performed at 77, and the image is displayed on the monitor 84 and output to the image recording device 86.

[0009]

However, in the endoscope image data compression apparatus of the image recording apparatus described above, the interpolation processing is performed as described above to compress the redundant image data. There is a disadvantage that the compression efficiency of image data is reduced.

The present invention has been made in view of the above points, and has as its object to provide an endoscope image data compression apparatus capable of efficiently compressing image data.

[0011]

An endoscope image data compressing apparatus according to the present invention has a predetermined number of pixels, an image pickup means for picking up an object image using an endoscope, and a pixel of the image pickup means.
Display means having a display area of the number of different pixels from the number, before
The input of the video signal generated based on the output signal of the imaging means.
Input terminal, and complements the video signal input from the input terminal.
And subject the subject image captured by the imaging means to
Display to be displayed corresponding to the display area of the display means
Signal processing means for generating a signal; and an output signal of the imaging means .
The video signal generated on the basis of the
And data compression means for data compressing the image signal, compression de the video signal data compressed by said data compression means
A compressed data recording means for recording a data signal, a data decompression means for outputting decompressed data signal the compressed data signal output <br/> decompressed to from the compressed data recording means, of the imaging unit The video generated based on the output signal
Image signal or the output from said data decompressing means,
Select the expanded data signal and input it to the input end of the signal processing means.
Signal input means for inputting .

[0012]

[Operation] In the above configuration, based on the output signal of the imaging means.
The generated video signal is input to the data compression means
The data is compressed and recorded in the compressed data recording means. This
The compressed data recorded in the compressed data recording means
Expanded data signal can be generated by data expansion means
And the expanded data signal or the output of the imaging means.
The video signal generated based on the input signal is selected by the selection means.
Input to the signal processing means .

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 relate to a first embodiment of the present invention. FIG. 1 is a configuration diagram of an electronic endoscope device, FIG. 2 is a configuration diagram of an image recording device, FIG. FIG. 4 is an explanatory diagram relating to a frequency distribution of prediction errors of an endoscope image.

As shown in FIG. 1, an electronic endoscope apparatus of a frame sequential imaging system includes a control signal generator 5 for generating a predetermined control signal for each block described later, and a solid-state image sensor for imaging a subject. CCD (charge coupled device) 1 and this CCD
An amplifier 2 that amplifies and processes the image signal of the camera 1 to convert it into a video signal, a gamma circuit 3 that gamma corrects the video signal amplified by the amplifier 2, and a video signal that is a gamma corrected analog signal described above. An analog-to-digital converter (hereinafter, referred to as an A / D converter) 4 that converts digital signal data according to a control signal of the control signal generator 5.
A terminal 10 for guiding the digital signal to an image recording apparatus described later; a lamp 7 for generating illumination light for supplying the CCD 1 with a portion to be imaged; ), G (green wavelength region) and B
(A blue wavelength region) a rotating filter 8 provided with a filter for separating light, a motor 6 for rotating the rotating filter 8 by a control signal of the control signal generating unit 5, and an illumination light separated as described above. A light guide 9 for guiding light to a part of the CCD 1 where an image is taken;
And a terminal 11 for deriving a synchronization signal (SYNC) generated by the above. The CCD 1 is connected to an input terminal of the amplifier 2, an output terminal of the amplifier 2 is connected to an input terminal of the γ circuit 3, and an output terminal of the γ circuit 3 is connected to the A terminal.
The output terminal of the D / A converter 4 is connected to the terminal 10.

The control signal input terminals of the A / D converter 4 and the motor 6 are connected to the output terminal of the control signal generator 5, respectively. One output terminal of the control signal generator 5 is connected to a terminal 11.

As shown in FIG. 2, the image recording apparatus includes, for example, a terminal 21 into which a time-series RGB video signal from the electronic endoscope apparatus is introduced, and a synchronizing signal (S
YNC), a switch 23a for switching whether or not to record a video signal introduced from the terminal 21 in a recording system unit to be described later, and the switch 23a
A data compression unit 24 for compressing a video signal introduced from the terminal 21 via the terminal 21, a recording system unit 26 such as an optical disk device for recording image data compressed by the data compression unit 24, and a recording system unit. When the image data recorded in the data compression unit 26 is reproduced, a data decompression unit 27 for restoring the image data compressed by the data compression unit 24, and a video signal from the data decompression unit 27 to an input terminal of a signal processing circuit described later. Or a switch 23b for switching to input a video signal introduced from the terminal 21 via the switch 23a;
b. A signal processing circuit 2 for performing a synchronization process, an interpolation process for converting to the number of pixels of a display unit, an analog-digital conversion process, and the like for a video signal switched and input according to b.
8, a display device 29 which is, for example, a monitor for displaying, for example, an RGB video signal processed by the signal processing circuit 28, and the data compression unit 24, the recording system unit based on a synchronization signal introduced from the terminal 22. 26, a control signal generator 2 for outputting a predetermined synchronization signal to the data decompressor 27, the signal processing circuit 28, and the display device 29
And 5.

The terminal 21 is connected to the transfer end of the switch 23a, the make end of the switch 23a is connected to the make end of the switch 23b, and the break end is connected to the input end of the data compression section 24. .

The output end of the data compression section 24 is connected to the input end of the recording system section 26, the output end of the recording system section 26 is connected to the input end of the data expansion section 27, and the data expansion section 27 The output end of the switch 2
3b, the transfer terminal of the switch 23b is connected to the input terminal of the signal processing circuit 28, and the output terminal of the signal processing circuit 28 is connected to the display device 29.
Is connected to the input terminal of

The terminal 22 is connected to an input terminal of the control signal generator 25, and the data compression unit 24, the recording system unit 26, the data decompression unit 27, and the signal processing circuit 2
8 and a synchronizing signal input terminal of the display device 29 are connected to an output terminal of the control signal generator 25, respectively.

The operation of the thus configured endoscope image data compression apparatus will be described.

The rotary filter 8 is rotated by the motor 6 which rotates in synchronization with the control signal of the control signal generator 5, and separates the illumination light of the lamp 7 into R, G and B light. The spectrally illuminated light is guided to the light guide 9 and illuminates an object (not shown). The luminous flux of the subject illuminated by the illumination light forms an image on the imaging surface of the CCD 1 by an objective lens system (not shown), is photoelectrically converted, and is input to the amplifier 2 as an imaging signal. The amplifier 2
Removes noise and the like from the above-described image pickup signal to form a video signal, amplifies the video signal so as to have a constant voltage range of, for example, 0 to 1 V, and outputs the amplified video signal to the γ circuit 3. The γ circuit 3 converts the video signal described above so as to have a gamma characteristic, and outputs the video signal to the A / D converter 4. A /
The D converter 4 converts the video signal having the above-described gamma characteristic into a digital signal of, for example, 8 bits, that is, quantizes and outputs the digital signal to the terminal 10. Further, the control signal generator 5 outputs a control signal to the motor 6 and the A / D converter 4 and outputs a synchronization signal (SYNC) to the terminal 11 so as to be able to be derived. Therefore, R, G, and B video signals based on digital signals can be derived in time series from the terminal 10, and a synchronization signal synchronized with the video signal can be derived from the terminal 11.

The video signal led out to the terminal 10 is introduced into the terminal 21 of the image recording device, and
The synchronization signal derived to 1 is introduced to the terminal 22 of the image recording apparatus.

The video signal introduced to the terminal 21 is input to the signal processing circuit 28 via the make ends of the switches 23a and 23b when the image recording device does not record the video signal, and R,
Processing such as G, B synchronization processing and interpolation processing for converting the number of pixels of the CCD 1 to the number of pixels of the display device 29 are performed, and the R, G, B, NTSC or luminance signal (Y ) And a color signal (C), and can be observed as an endoscope image by the display device 29.

The video signal introduced to the terminal 21 is input to the input terminal of the data signal compression unit 24 through the break terminal of the switch 23a when the image recording device records the video signal. , The data signal compression unit 2
The data is compressed by, for example, a predictive coding method and output to the recording system unit 26, and is recorded by the recording system unit 26 on a recording medium such as an optical disk or a magnetic disk.

The above-described predictive coding method will be described with reference to FIGS.

FIG. 3 shows a signal of a certain n line and its ± 1 line. According to this, the n-1 line is already read and the value is known, and the n line is
The pixel is read up to the pixel of interest x, the value up to the pixel x is known, and the value of all n + 1 lines is unknown.

Here, the pixel in the horizontal direction -1 of the pixel of interest x is a, the pixel in the vertical direction of the pixel of interest, that is, the pixel at the same horizontal position in the n-1 line is c, b,
Assuming that a pixel in the horizontal direction +1 of c is d, the previous value prediction expression (previous value), the average prediction expression (average), and the composite prediction expression (composite)
The predicted value x ′ is as follows.

X ′ = a (previous value) x ′ = 1/2 (a + d) (average) x ′ = 3 / 4a + 1 / 4d + 1 / 2c−1 / 2d (composite) It looks like this: Δx = xx ′ ◎ Accordingly, by recording the prediction error Δx, the data x of the original image can be restored from the known data. Also,
Generally, the prediction error Δx has a smaller value than the original image x, so that information can be compressed.

FIG. 4 shows an example of the frequency distribution of the observed image. When the prediction is performed correctly, the prediction error is zero, and when the prediction value is larger than the true value, the prediction error is +
If it is small, the prediction error is distributed to-.

FIG. 4 shows the frequency distribution of a normal observed image. FIG. 4 (a) shows the case where the previous value prediction formula is used. FIG. 4 (b) shows the case where the average prediction formula is used. FIG. 4
(C) shows a case where a composite prediction formula is used. In a normal observation image, since the correlation between adjacent pixels is high and the high-frequency component is small, the frequency distribution is concentrated on a portion where the frequency distribution is close to zero even if the prediction formula is different. Therefore, even if a simple expression such as the previous value prediction expression is used, the compression can be sufficiently performed.

When a special observation such as staining is performed and this observation image is compressed, it is more efficient to use the average prediction formula or the composite prediction formula depending on the correlation between adjacent pixels of the observation image. Compression may be possible.

The data compression section 24 compresses the video signal using a plurality of prediction formulas, for example, as described above.

When the image data recorded on the recording medium of the recording system unit 26 is displayed by the display device 29, the R, G,
B, and sequentially reads out the image data of
Expands (decodes) the compressed image data and outputs it to the signal processing circuit 28 via the break contact of the switch 23b.

In the signal processing circuit 28, the R, G, B synchronizing process and the number of pixels of the CCD 1 are
Interpolation processing for converting to the number of pixels and digital-analog conversion processing and the like are performed, and RGB,
It is output as NTSC or a luminance signal (Y) and a color signal (C), and can be observed as an endoscope image by the display device 29.

The image data is compressed by the data compressing section 24, the recording and reproducing of the compressed image data by the recording system section 26, the decoding of the compressed image data by the data expanding section 27, the signal processing circuit 28
Signal processing such as interpolation processing by the display device 29
Is displayed in synchronization with a synchronization signal from the control signal generator 25.

That is, when image data is recorded in the recording system unit 26, the image data is data that has not been subjected to interpolation processing to become redundant data, and can be efficiently compressed. Since a digital image signal is compressed instead of an analog image signal output to a display device, noise components due to analog-digital conversion or the like can be reduced, and a high-quality image signal can be recorded. This has the effect.

FIGS. 5 and 6 relate to a second embodiment of the present invention. FIG. 5 is a configuration diagram of an electronic endoscope device, and FIG. 6 is a configuration diagram of an image recording device. Note that the same components as those in the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted.

As shown in FIG. 5, the electronic endoscope apparatus of this embodiment is similar to the electronic endoscope apparatus of the first embodiment except that R, G,
A memory unit 15 for synchronizing the time-series video signal of B;
The video signal converted into a digital signal by the / D converter 4 is stored in the R memory 15R and the G memory 1 of the memory unit 15.
5G and a selector 12 for distributing to the B memory 15B, and terminals 10R and 10 for deriving an image signal synchronized by the R memory 15R, the G memory 15G, and the B memory 15B.
G and 10B.

The selector 12 has an input terminal connected to an input terminal of the A / D converter 4, and an output terminal connected to the R memory 15R, the G memory 15G, and the B memory 15 respectively.
B is connected to the input terminal. An output terminal of the R memory 15R is connected to a terminal 10R for deriving an R video signal, an output terminal of the G memory 15G is connected to a terminal 10G for deriving a G video signal, and an output terminal of the B memory 15B is connected to a B video signal. It is connected to a terminal 10B for deriving a signal. Also,
Control signal input terminals of the selector 12 and the memory unit 15 are connected to output terminals of the control signal generation unit 5, respectively.

As shown in FIG. 6, the recording apparatus according to the present embodiment includes, for example, a synchronized RG from the electronic endoscope apparatus.
Terminals 21R, 21G, 21B into which B video signal is introduced
A terminal 22 to which the above-mentioned video signal synchronization signal (SYNC) is introduced, and a switch 23aR for switching whether or not the video signal introduced from the terminals 21R, 21G, 21B is recorded in a recording system section described later. 23aG, 23aB
And an R data compression unit 24 for compressing an R video signal introduced from the terminal 21R through the switch 23aR.
R, a G data compression unit 24G that compresses a G video signal introduced from the terminal 21G via the switch 23aG.
And a B data compression unit 24B for compressing a B video signal introduced from the terminal 21B via the switch 23aB.
A data compression unit 24 ', a recording system unit 26' such as an optical disk device for recording image data compressed by the data compression unit 24 ', and image data recorded on the recording system unit 26'. Is reproduced, the R data decompression unit 27R for restoring the R image data compressed by the R data compression unit 24R, the G data decompression unit 27G for restoring the G image data compressed by the G data compression unit 24G, and B data compression unit 24B
A data expansion unit 27 'composed of a B data expansion unit 27B for restoring the B image data compressed by the above-mentioned method, and a video signal from the data expansion unit 27' or the terminal 21R, The switches 23aR, 23aG, 23aB introduced from 21G, 21B
Switches 23bR, 23bG, 23bB for switching to input a video signal via the
A processing circuit 2 that performs an interpolation process for converting the video signal switched and input by R, 23bG, and 23bB into the number of pixels of the display unit 29, an analog-digital conversion process, and the like.
8 ′, a display device 29 which is, for example, a monitor for displaying, for example, an RGB video signal processed by the signal processing circuit 28 ′, and the data compression unit 24 ′, Recording system part 2
6 ', the data decompression unit 27', the signal processing circuit 2
8 'and a control signal generator 25 for outputting a predetermined synchronizing signal to the display device 29.

The terminals 21R, 21G, 21B are respectively connected to transfer ends of the switches 23aR, 23aG, 23aB, the switch 23aR has a make end connected to the make end of the switch 23bR, and a break end has the R data compression. The switch 23aG has a make end connected to the make end of the switch 23bG, a break end connected to an input end of the G data compression unit 24G, and the switch 23aB has a make end connected to the input end of the switch 23bG. Connected to the makeup end of switch 23bB,
The break end is connected to the input end of the B data compression unit 24B.

The output terminals of the R data compression unit 24R, the G data compression unit 24G, and the B data compression unit 24B are respectively connected to the input terminals of the recording system unit 26 ', and the output terminals of the recording system unit 26' are each connected. The R data decompression unit 27
The R and G data decompression units 27G and 27B are connected to the input terminals of the B data decompression unit 27B, and the output terminal of the R data decompression unit 27R is connected to the break end of the switch 23bR.
The output end of the data decompression unit 27G is connected to the break end of the switch 23bG, the output end of the B data decompression unit 27B is connected to the break end of the switch 23bB,
The transfer terminals of the switches 23bR, 23bG and 23bB are connected to the input terminals of the signal processing circuit 28 ', respectively, and the output terminals of the signal processing circuits 28' are connected to the input terminals of the display device 29. The terminal 22 is connected to an input terminal of the control signal generation unit 25, and synchronizes the data compression unit 24 ', the recording system unit 26', the data decompression unit 27 ', the signal processing circuit 28', and the display device 29. The signal input terminals are connected to the output terminals of the control signal generator 25, respectively.

The operation of the thus configured endoscope image data compression apparatus will be described. CC as in the first embodiment
A video signal captured by D1 and quantized by the A / D converter 4 to become a digital signal is switched by the selector 12 for each of R, G, and B corresponding to the illumination light, and is output to the R memory 15R and the G memory. 15G and B memory 15B, and the R memory 15R and the G memory 15
The terminals 10R,
It is output so that it can be derived from 10G and 10B.

The above-mentioned video signals from the terminals 10R, 10G and 10B are supplied to the terminal 21 of the image recording apparatus.
R, 21G, and 21B, and the above-mentioned synchronization signal led out to the terminal 11 is applied to the terminal 2 of the image recording apparatus.
2 is introduced. When the image recording device does not record the video signal, the video signals introduced to the terminals 21R, 21G, and 21B are transmitted to the switches 23aR, 23bR, and 2b.
The signal processing circuit 28 ′ is inputted to the signal processing circuit 28 ′ via the respective makeup ends of 3 aG, 23 bG, 23 aB and 23 bB, and the signal processing circuit 28 ′ converts the number of pixels of the CCD 1 to the number of pixels of the display device 29. Is output to the display device 29 as R, G, B, NTSC or a luminance signal (Y) and a color signal (C).
9 enables observation as an endoscope image.

The video signals introduced into the terminals 21R, 21G, 21B are used when the image recording device records the video signals, by the switches 23aR, 23aG, 2B.
The data signal compression unit 24 is connected via a 3aB break end.
R data compression section 24R, G data compression section 24G and B
The data are input to the input terminals of the data compression unit 24B, respectively, and compressed by the data signal compression unit 24 ', for example, according to the predictive coding method described in the first embodiment, and the recording system unit 26' is used.
And recorded on a recording medium such as an optical disk or a magnetic disk by the recording system unit 26 '.

When the image data recorded on the recording medium of the recording system unit 26 'is displayed by the display device 29, R, R
G and B image data are read out, and the data
The image data compressed by the R data decompression unit 27R, G data decompression unit 27G, and B data decompression unit 27B of 7 'is decompressed (decoded), and the switches 23bR, 23bG, and 2b are decompressed.
The signal processing circuit 28 'is connected via a 3bB break contact.
Output to

In the signal processing circuit 28 ', the CCD
Interpolation processing for converting the number of pixels of 1 into the number of pixels of the display device 29 and processing such as digital-analog conversion are performed, and RGB, NTSC or a luminance signal (Y) and a color signal (C) are supplied to the display device 29. And can be observed as an endoscope image by the display device 29.

The image data is compressed by the data compression unit 24 ', the recording and reproduction of the image data compressed by the recording system unit 26', and the data decompression unit 2 '
The decoding of the compressed image data by 7 ', the various signal processing such as the interpolation processing by the signal processing circuit 28', and the display of the observation image or the reproduced image by the display device 29 are performed by the synchronization signal from the control signal generator 25. It is performed synchronously.

That is, it is possible to perform compression corresponding to each of the R, G, and B image signals, thereby improving the compression efficiency of image data. Other configurations, operations and effects are the same as those of the first embodiment.

FIG. 7 is a block diagram of an electronic endoscope apparatus according to a modification of the second embodiment. The electronic endoscope apparatus according to the present modification differs from the electronic endoscope apparatus according to the second embodiment in that R, G, and B video signals are converted into a luminance signal (Y) and color difference signals (RY, BY). A matrix circuit 16 is provided, and terminals 10Y, 10RY, and 10BY for deriving the luminance signal and the color difference signal converted by the matrix circuit 16 are provided.

The above-mentioned luminance signal and color difference signal from the terminals 10Y, 10RY and 10BY are recorded, reproduced or displayed by the image recording apparatus described in the second embodiment. Therefore, the image recording apparatus described in the second embodiment may compress and decompress an image signal based on a luminance signal and a chrominance signal, and may also compress and decompress an image signal divided into other wavelength regions, for example. Good. Other configurations, operations, and effects are the same as those of the second embodiment, and the same reference numerals are given and the description is omitted.

8 to 11 relate to a third embodiment of the present invention. FIG. 8 is a block diagram of an electronic endoscope device, FIG. 9 is a block diagram of an image recording device, and FIG. 10 is an A / D converter and data. FIG. 11 is an explanatory diagram showing the relationship between sampling with the sample unit, and FIG. 11 is an explanatory diagram showing the relationship between input pixels and output pixels of the data sample unit. As shown in FIG. 8, an electronic endoscope apparatus of a plane sequential imaging system includes a control signal generation unit 120 that generates a predetermined control signal in each block described later, and a CCD (charged) that is a solid-state imaging device that captures an image of a subject. Coupling element) 101 and this CC
An amplifier 102 that amplifies and processes the image pickup signal of D101 to convert the image signal into a video signal; a gamma circuit 103 that performs gamma correction on the video signal amplified by the amplifier 102;
A / D converter 104 for converting a corrected analog video signal into a digital signal data in accordance with a control signal of the control signal generator 120, and R, G, B output by the A / D converter 104 A memory unit 106 for synchronizing a series of video signals, and an A / D converter 104
The video signal converted into a digital signal by the R memory 106R, the G memory 106G, and the B memory
A selector 105 for distributing to the memory 106B, and terminals 107R and 1 for deriving image signals synchronized by the R memory 106R, the G memory 106G, and the B memory 106B.
07G and 107B.

The input terminal of the selector 105 is the A / D converter.
The input terminal of the converter 104 is connected to the R memory 106R, the G memory 106G, and the B terminal.
It is connected to the input terminal of the memory 106B. An output terminal of the R memory 106R is a terminal 107 for deriving an R video signal.
The output terminal of the G memory 106G is connected to a terminal 107G for deriving a G video signal, and the output terminal of the B memory 106B is connected to a terminal 107B for deriving a B video signal.
It is connected to the.

In addition, the electronic endoscope apparatus may include the CCD
A lamp 122 for generating illumination light for supplying to a part or the like to be imaged by 101, and a filter for dispersing the light of the lamp 122 into R (red wavelength region), G (green wavelength region), and B (blue wavelength region) Rotary filter 12 provided with
3 and the control signal generator 1
20, a light guide 124 for guiding the separated illumination light to an area where the CCD 101 captures an image, and a synchronization signal generated by the control signal generation unit 120. SYNC).

Further, the electronic endoscope apparatus may include the CC
A CCD detector 125 for determining the type of D101, and an output signal of the CCD detector 125 is supplied to the control signal generator 1
20 according to a predetermined timing from the CCD detection signal
A CCD detection signal generator 126 for generating (CSIG) and a terminal 128 for introducing a CCD detection signal output by the CCD detection signal generator 126 are provided.

A / D converter 104, selector 1
05, a control signal input terminal of the memory unit 106, the motor 121, and a control signal input terminal of the CCD detection signal generation unit 126 are connected to an output terminal of the control signal generation unit 120, respectively.

As shown in FIG. 9, the image recording apparatus according to the present embodiment uses, for example, a synchronized R from the electronic endoscope apparatus.
Terminals 130R, 130G, into which GB video signals are introduced,
130B, a terminal 140 to which the above-mentioned video signal synchronization signal (SYNC) is introduced, a terminal 140 to which the above-mentioned CCD detection signal (CSIG) is introduced, and the terminals 130R and 130R.
Switch 131 for switching whether or not to record the video signal introduced from G and 130B in a recording system unit to be described later
R, 131G, and 131B, an R data sampler 132R that samples an R video signal introduced from the terminal 130R through the switch 131R, and the switch 131G.
From the G data sampling unit 132G sampling the G video signal introduced from the terminal 130G via the switch 130B, and from the B data sampling unit 132B sampling the B video signal introduced from the terminal 130B via the switch 131B. A data sampling unit 132 ', an R data compression unit 133R for compressing a sampled R video signal introduced from the data sampling unit 132R, and the data sampling unit 132
G that compresses the sampled G video signal introduced from G
A data compression unit 133G and the data sampling unit 132B
Data compression unit 13 composed of a B data compression unit 133B for compressing a sampled B video signal introduced from
3 ', and a recording system unit 134' which is, for example, an optical disk device for recording the image data compressed by the data compression unit 133 '.

When reproducing the image data recorded in the recording system section 134 ', the image recording apparatus includes an R data expansion section 135R for restoring the R image data compressed by the R data compression section 133R. A G data decompression unit 135G for restoring G image data compressed by the G data compression unit 133G, and a B for restoring B image data compressed by the B data compression unit 133B.
Data decompression unit 1 composed of data decompression unit 135B
35 ′, and R for reproducing the R image data restored by the R data decompression unit 135R to the size before sampling.
A data interpolation unit 136R, a G data interpolation unit 136G that reproduces the G image data restored by the G data expansion unit 135G to a size before sampling, and the data expansion unit 1
And a data interpolating unit 136 'composed of a B data interpolating unit 136B for reproducing the B image data restored by the 35B to the size before sampling.

Further, the image recording apparatus is provided with a video signal from the data interpolation unit 136 'or the terminals 130R, 130G, 130B to an input terminal of a signal processing circuit described later.
Switches 131R, 131G, 131
B, switches 137R, 137G, 137B for inputting a video signal via B;
7R, 137G, 137B, a processing circuit 138 'for performing an interpolation process for converting the input video signal into the number of pixels of the display means 139 and an analog-digital conversion process, and a signal processing circuit 138'. A display device 139 that displays, for example, a processed RGB video signal, for example, a monitor, a synchronization signal introduced from the terminal 140, and a CC introduced from the terminal 141.
From the D detection signal to the data sample section 132 ', the data compression section 133', the recording system section 134, the data decompression section 135 ', the data interpolation section 136', the signal processing circuit 138 ', and the display device 139. A control signal generator 142 for outputting a predetermined synchronization signal.

With such a configuration, the A / D converter 10
4, the R, G, B time-series image data converted into digital data is input to the selector 105, and the output of the selector 105 is stored in the memories 106R, 106G, 106B.
The time-series image data is synchronized by sequentially inputting and writing the image data and reading the respective image data from the memory 106 at the same time. The read R, G, and B image data synchronized in the memory 106 is supplied to terminals 130R and 130R.
G, 130B, and sent to the image recording apparatus, and a synchronizing signal and a CCD detection signal are supplied to terminals 1 and 2, respectively.
The image data is sent to the same image recording device via 40 and 141.

If the image recording device does not record the video signal, the R, G, B transmitted from the electronic endoscope device
The synchronized video signals are transmitted to the switches 131R and 13R.
1R, 131G, 137G, 137B, 137B are input to the signal processing circuit 138 'through the make ends, and the signal processing circuit 138' converts the number of pixels of the CCD 101 to the number of pixels of the display device 139. And the like, and R, G, B, NT
It is output as SC or a luminance signal (Y) and a color signal (C), and can be observed as an endoscope image by the display device 139.

When recording an image signal, the image recording device transmits the image signal sent from the electronic endoscope apparatus to the data signal compression section via the break ends of the switches 130R, 130G, and 130B. The R data sample 132R, the G data sample unit 132G, and the B data sample 132B are respectively input to the input terminals of the 24 R data samples 132R, G data sample units 132G, and B data samples 132B. Data sampler 13
In 2 ', sampling is performed again to extract necessary pixel data according to the CCD detection signal from the electronic endoscope apparatus. For example, as shown in FIG. 10, when the sampling frequency of the A / D converter 104 is n times (two times in the illustrated example) the driving frequency of the CCD 101, the same level value is sampled n times. This means that it is converted to digital data. Therefore, as shown in FIG.
In the data sampling unit 132 ′, in order to avoid duplication of the same data, sampling is performed again to extract only data デ ー タ necessary for the input data.

Then, the R, G, B image signals extracted by the data sampling section 132 'are converted into data compression sections 133'.
Thus, for example, the data is compressed by the predictive coding method described in the first embodiment and output to the recording system unit 134,
The data is recorded on a recording medium such as an optical disk or a magnetic disk by the recording system unit 134.

When the image data recorded on the recording medium of the recording system section 134 is displayed by the display device 139, the R, G, B image data recorded by the recording system section 134 is read and the data expansion is performed. R data expansion unit 135R and G data expansion unit 1 of the unit 135 '
The image data compressed by the 35G and B data expansion unit 135B is expanded (decoded) and sent to the data interpolation unit 136 '. R decompressed by the data decompression unit 135 ',
The G and B image data are stored in the R
Data interpolation unit 136R, G data interpolation units 136G and B
The data is reproduced to the size of the CCD 101 before sampling by the data interpolation 136B, and the switches 137R, 137G,
137B, the signal processing circuit 1
38.

In the signal processing circuit 138, the CCD
Interpolation processing for converting the number of pixels 101 into the number of pixels of the display device 139 and digital-to-analog conversion processing are performed, and RGB, NTSC or a luminance signal (Y) and a color signal (C) are applied to the display device 139. And can be observed as an endoscope image by the display device 139.

The image data compression by the data compression unit 133 ′, the recording and reproduction of the image data compressed by the recording system unit 134, the data decompression unit 1
Decoding of compressed image data by 35 ', reproduction of image data to the size before sampling by the data interpolation unit 136', various signal processing such as interpolation by the signal processing circuit 138 ', and observation by the display device 139. The display of the image or the reproduced image is performed in synchronization with the synchronization signal from the control signal generator 142.

That is, since the type of CCD is identified and the image data is compressed after sampling in order to eliminate the duplicated identical data, the R, G, and B are further compared to the second embodiment. Compression corresponding to each image signal can be performed, and the compression efficiency of image data can be improved.

Although an electronic endoscope has been described as the image signal input means, the image input means may be an image input means in which an external television camera device is attached to an endoscope using an image guide, for example. In addition, the compression means is not limited to the method under the predictive code, but the discrete cosine transform (DCT) method,
Known compression means such as a vector quantization method may be used.

[0069]

As described above, according to the present invention, there is an effect that the data of a captured image can be efficiently compressed without damaging the image.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an electronic endoscope apparatus according to a first embodiment.

FIG. 2 is a configuration diagram of an image recording apparatus.

FIG. 3 is an explanatory diagram related to predictive coding.

FIG. 4 is an explanatory diagram relating to a frequency distribution of prediction errors of an endoscope image.

FIG. 5 is a configuration diagram of an electronic endoscope apparatus according to a second embodiment of the present invention.

FIG. 6 is a configuration diagram of an image recording apparatus.

FIG. 7 is a configuration diagram of an electronic endoscope apparatus according to a modification of the second embodiment.

FIG. 8 is a configuration diagram of an electronic endoscope apparatus according to a third embodiment of the present invention.

FIG. 9 is a configuration diagram of an image recording apparatus.

FIG. 10 is an explanatory diagram showing a sampling relationship between an A / D converter and a data sample unit.

FIG. 11 is an explanatory diagram showing a relationship between input pixels and output pixels of a data sample unit.

FIG. 12 is a configuration diagram of an entire endoscope system according to a conventional technique.

FIG. 13 is a configuration diagram of an electronic endoscope apparatus.

FIG. 14 is a configuration diagram of an image recording apparatus.

FIG. 15 is an explanatory diagram relating to the number of pixels of a CCD and a monitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... CCD 24 ... Data compression part 26 ... Recording system part 27 ... Data decompression part 28 ... Signal processing circuit

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) A61B 1/00-1/32 G02B 23/24-23/26 G06T 1/00 H04N 7/18 H04N 5 / 76-5/956

Claims (1)

(57) [Claims] 1. An imaging device having a predetermined number of pixels and capturing an image of a subject using an endoscope, and a display area having a number of pixels different from the number of pixels of the imaging device.
Display means for displaying, and a video signal generated based on an output signal of the imaging means.
An input terminal, and the video signal input from the input terminal is
The subject image picked up by the image pickup unit after the interpolation processing
Table corresponding to the display area of the display means.
Signal processing means for generating an indication signal; and the video signal generated based on an output signal of the imaging means.
No. is input, and data compression means for data compressing the video signal, the video signal data compressed by said data compression means
A compressed data recording means for recording the compressed data signal, the compressed data output from the compressed data recording means
A data decompression means for outputting decompressed data signals to decompression processing the signal, the video signal which is generated based on the output signal of the imaging means
No. The stretch or outputted from the data decompression means,
Select a data signal and input to the input terminal of the signal processing means
An endoscope image data compression device, comprising: